Polyketone from carbon monoxide and mixture of olefins

ABSTRACT

The invention is a linear random terpolymer comprised of repeating units of --CO--(C 2  H 4 )-- and units of --CO--(C x  H y )-- where x is greater than 2 and less than 20, having a melting point between about 150° C. and about 245° C. The invention also concerns a process to prepare a polymer having a melting point less than about 245° C. which comprises contacting carbon monoxide and ethylene in the presence of one or more hydrocarbons C x  H y  containing an olefinically unsaturated --CH═CH-- group, where x is greater than 2 and less than 20, with a suitable catalyst and under conditions effective to prepare a linear random polymer having units of the formula --CO--(C 2  H 4 )-- and units of the general formula --CO--(C x  H y )--, and having a melting point less than about 245° C.

This is a division of application Ser. No. 190,607, filed May 5, 1988,which is a continuation of Ser. No. 901,917, filed Aug. 28, 1986, nowabandoned.

FIELD OF THE INVENTION

The invention relates to new terpolymers of carbon monoxide withethylene and with one or more other olefinically unsaturatedhydrocarbons, and to a process for their preparation.

BACKGROUND OF THE INVENTION

Copolymers of carbon monoxide and olefins, such as ethylene, have beenknown and available in limited quantities for many years. They areusually prepared by reacting the CO and ethylene monomers in thepresence of a catalyst. High molecular weight polymers of ethylene whichcontain small quantities of carbon monoxide can be prepared with the aidof Ziegler catalysts. Low molecular weight polymers of carbon monoxidewith ethylene and possibly other olefinically unsaturated hydrocarbonsin which all monomer units occur distributed at random within thepolymer can be prepared with the aid of radical catalysts such asperoxides. A special class of the copolymers of carbon monoxide withethylene is formed of the high molecular weight linear copolymers inwhich the monomer units occur in alternating order in units with theformula --CO--(C₂ H₄)--. Such polymers can be prepared with the aid of,among others, phosphorus-, arsenic-, antimony-, or cyanogen-containingcompounds of palladium, cobalt or nickel as catalysts.

The high molecular weight linear alternating polymers of carbon monoxidewith ethylene have excellent mechanical properties, in particular veryhigh strength, rigidity and impact-resistance. Due primarily to the highmelting point of these polymers, about 257° C., there exist considerableproblems in their processing. The processing of these polymers, forexample, injection-molding, should take place in a molten state, thematerial being at a temperature of at least 25° C. above its meltingpoint, i.e. at a temperature of above 280° C. It has been found thatthese polymers cannot withstand such high temperatures. Seriousdiscoloration and decomposition of the polymers takes place. The highdegree of gelling greatly hinders the processing of the polymers.

Attempts have been made in the past to lower the melting point of thepolymers through chemical reactions to enable them to be processed at alower temperature. Examples of such chemical reactions are those inwhich part of the carbonyl groups present in the polymers are convertedinto furan-, pyrrol-, thio- or thioketal groups. Although theabove-mentioned methods can in a number of cases achieve a considerablereduction of the melting point of the polymers and thus lower therequired processing temperature correspondingly, the thermal stabilityof the polymers is often reduced as a result of the chemicalmodification to such an extent that the previously mentioned problemssuch as discloration, decomposition and gelling occur to practically thesame extent, except now at a lower processing temperature.

It should be noted from the above discussion that no solution has yetbeen found for the problems outlined in processing the polyketones andthat there is still an urgent need for a method of lowering the meltingpoint of the polyketone polymers which does not at the same time greatlyreduce their thermal stability.

Surprisingly, it has now been found that it is possible to reduce themelting point of the polymers to a value of between 150° and 245° C.without serious detriment to the thermal stability of the polymers byincluding in the monomer mixture from which the polymers are prepared,in addition to carbon monoxide and ethylene, a relatively small quantityof one or more other polymerizable hydrocarbons. Polymerizablehydrocarbons suitable for this purpose have the general formula C_(x)H_(y) in which x is smaller than 20 and contain an olefinicallyunsaturated --CH═CH-- group. If a catalyst is employed, such as thepreviously mentioned palladium, nickel and cobalt compounds enabling ahigh molecular weight linear alternating polymer to be prepared from amixture of carbon monoxide and ethylene, the copolymer will consist ofunits with the formula --CO--(C₂ H₄)--. If the same catalyst is employedand the compound with the general formula C_(x) H_(y) is included in theco/ethylene monomer mixture, a terpolymer will be formed containingunits with the formula --CO--(C₂ H₄ )-- and different units with thegeneral formula --CO--(C_(x) H_(y))-- distributed randomly within thepolymer. The structure of the two polymers differs only in that in thesecond case a --(C_(x) H_(y))-- group is encountered instead of a --(C₂H₄)-- group at some random points in the polymer. The surprising resultof this structural change is that the melting point is reduced withoutserious detriment to the thermal stability.

The extent of the melting point reduction depends, among other things,on the value of the quotient m/n, where m represents the mean number ofunits with the general formula --CO--(C_(x) H_(y))-- and n representsthe mean number of units with the formula --CO--(C₂ H₄)-- in thepolymer. For polymers of carbon monoxide with ethylene and with a givenmonomer with the general formula C_(x) H_(y), this dependence means thatif n changes, m must change proportionally in order to achieve the samemelting point reduction, and that if n is constant, a larger or smallermelting point reduction will be observed as m increases or decreases. Inaddition, it has been found that the extent of the melting pointreduction also depends on the molecular weight of the monomers with thegeneral formula C_(x) H_(y). Finally, the extent of the melting pointreduction also depends on the structure of the monomers with the generalformula C_(x) H_(y) used in the preparation of the terpolymers.

SUMMARY OF THE INVENTION

The present invention is a polymer of CO, ethylene, and one or morehydrocarbons, which hydrocarbons have the general formula C_(x) H_(y)where x is greater than 2 and less than 20, y is 2x, and whichhydrocarbons contain an olefinically unsaturated --CH═CH-- group, andwhich polymer comprises:

(a) a linear structure,

(b) units of the formula --CO--(C₂ H₄)-- and units of the generalformula --CO--(C_(x) H_(y))-- where x is greater than 2 and less than20,

(c) random distribution of said units in the polymer, and

(d) a melting point between about 150° C. and about 245° C. Theinvention includes shaped objects consisting at least partly of thesepolymers.

The invention also concerns a process for preparing a polyketone havinga melting point less than 245° C. which comprises contacting carbonmonoxide and ethylene in the presence of one or more olefinichydrocarbons of the general formula C_(x) H_(y) where x is greater than2 and less than 20 and containing an olefinically unsaturated --CH═CH--group, with a suitable catalyst and under conditions effective toprepare a linear random polymer having units of the formula --CO--(C₂H₄)-- and units of the general formula --CO--(C_(x) H_(y))--, and amelting point less than about 245° C. and recovering a polymer having amelting point less than about 245° C.

The invention further relates to a process to prepare a linear randompolymer having units of the formula --CO--(C₂ H₄)-- and units of thegeneral formula --CO--(C_(x) H_(y))--, having a melting point less thanabout 245° C., which process comprises contacting carbon monoxide andethylene in the presence of one or more olefinic hydrocarbons of thegeneral formula C_(x) H_(y) where x is greater than 2 and less than 20and containing an olefinically unsaturated --CH═CH-- group, with acatalyst wherein the catalyst is a complex compound that is obtained byreacting (1) a Group VIII metal compound, (2) a bidentate ligand of thegeneral formula ##STR1## in which M is a Group Va element selected fromthe group consisting of phosphorus, arsenic, and antimony, R¹, R², R³,and R⁴ are identical or different hydrocarbon groups, R represents adivalent organic bridging group having at least two carbon atoms in thebridge, wherein the carbon atoms of the bridging group R do not containsubstituents that would sterically hinder formation of the complexcompound, and (3) an anion of an acid with a pKa of less than 2,provided said acid is not a hydrohalogenic acid, performing said processunder conditions suitable for preparing a linear random polymer havingunits of the formula --CO--(C₂ H₄)-- and units of the general formula--CO--(C_(x) H_(y))--, having a melting point less than 245° C., andrecovering a linear random polymer having units of the formula --CO--(C₂H₄)-- and units of the general formula --CO--(C_(x) H_(y))--, and havinga melting point less than about 245° C.

DETAILED DESCRIPTION OF THE INVENTION

The terpolymers according to the invention have a melting point ofbetween 150° and 245° C. Preferred terpolymers have a melting point ofbetween 170° and 240° C. and in particular between 195° and 235° C. Aspointed out above, the extent of the melting point reduction depends on,among other things, the value of the quotient m/n. For example, forterpolymers according to the invention prepared by polymerization ofcarbon monoxide with ethylene and with propylene and which consist of anaverage of n units with the formula --CO--(C₂ H₄)-- and an average of munits with the formula --CO--(C₃ H₆)--, a melting point of 245° C.corresponds to an m/n quotient of about 0.023, whereas a melting pointof 150° C. corresponds to an m/n quotient of about 0.33. As also pointedout above, the extent of the melting point reduction also depends on themolecular weight of the monomers with the general formula C_(x) H.sub. yused in the preparation of the terpolymers. For example, for aterpolymer according to the invention that is prepared by polymerizationof carbon monoxide with ethylene and with butylene-1 and that consistsof an average of n units with the formula --CO--(C₂ H₄)-- and an averageof m units with the formula --CO--(C₄ H₈)--, a melting point of 244° C.corresponds to an m/n quotient of about 0.007, while for a terpolymer ofcarbon monoxide with ethylene and with propylene a melting point of 244°C. corresponds to an m/n quotient of about 0.026. Furthermore, for aterpolymer according to the invention that is prepared by polymerizationof carbon monoxide with ethylene and with octylene-1 and that consistsof an average of n units with the formula --CO--(C₂ H₄)-- and an averageof m units with the formula --CO--(C₈ H₁₆)--, a melting point of 225° C.corresponds to an m/n quotient of about 0.057, whereas for a terpolymerof carbon monoxide with ethylene and with propylene a melting point of225° C. corresponds to an m/n quotient of about 0.068.

The higher the molecular weight of the terpolymers according to theinvention, the higher will be in general the intrinsic viscosity theyexhibit. For the determination of the intrinsic viscosity of aterpolymer according to the invention, four solutions are first of allprepared by dissolving the polymer in four different concentrations at100° C. in m-cresol. For each of these solutions, the viscosity ismeasured in a viscometer at 100° C. relative to m-cresol at 100° C. IfT_(o) represents the outflow time of m-cresol and T_(p) the outflow timeof the terpolymer solution, the relative viscosity (η_(rel)) is obtainedfrom η_(rel) =T_(o) /T_(p). From η_(rel) can be calculated the inherentviscosity (η_(inh)) according to the formula: η_(inh) (ln η_(rel))/cwhere c represents the concentration of the terpolymer in grams per 100ml solution. By plotting graphically the η_(inh) found for each of thefour terpolymer solutions against the corresponding concentration (c)and then by extrapolating to c=0, the intrinsic viscosity (η) in dl/g isfound. Instead of "intrinsic viscosity", this patent application willhenceforth use the term recommended by the International Union of Pureand Applied Chemistry, vis. "Limiting Viscosity Number" (LVN). Theterpolymers according to the invention generally have an LVN of between0.2 and 5.0 dl/g. Preferred terpolymers have an LVN of between 0.3 and4.5 dl/g and in particular an LVN of between 0.4 and 4.0 dl/g.

As mentioned before, the terpolymers according to the invention consistof units with the formula --CO--(C₂ H₄)-- and units with the generalformula --CO--(C_(x) H_(y))-- where x is smaller than 20. The units withthe general formula --CO--(C_(x) H_(y))-- which are present in thepolymers according to the invention can be the same or different fromone another. The latter will apply if, for example, the polymers areprepared from a monomer mixture in which, besides carbon monoxide andethylene, two or more other olefinically unsaturated hydrocarbons arepresent. For example, from a monomer mixture containing, in addition tocarbon monoxide and ethylene, both propylene and butylene, polymers areobtained which contain units with the formula --CO--(C₃ H₆)-- as well asunits with the formula --CO--(C₄ H₈)--. But even if the mixture to bepolymerized contains only one other olefinically unsaturatedhydrocarbon, different units with the general formula --CO--(C_(x)H_(y))-- may be present in the prepared polymer. In this case, thenumbers of carbon and hydrogen atoms in the various units will be thesame, but they will differ in structure. For example, when usingpropylene, units with the formula --CO--CH(CH₃)--CH₂ -- and units withthe formula --CO--CH₂ --CH(CH₃)-- may both be present. When usingolefins with more carbon atoms than propylene, such as butylene,pentylene or octylene, there will, in addition to the structuraldifferences as described for propylene, also be structural differencesas a result of isomerization. For example, when using pentene-1, unitswith the following formulae can occur in the prepared polymer.

    --CO--CH(C.sub.3 H.sub.7)--CH.sub.2 --

    --CO--CH.sub.2 --CH(C.sub.3 H.sub.7)--

    --CO--CH(CH.sub.3)--CH(C.sub.2 H.sub.5)--

    --CO--CH(C.sub.2 H.sub.5)--CH(CH.sub.3)--

Preferred terpolymers are those in which all units with the generalformula --CO--(C_(x) H_(y))-- have the same x and y. Such terpolymerscan be prepared from a monomer mixture that in addition to carbonmonoxide and ethylene only contains one other unsaturated hydrocarbon.Terpolymers are also preferred in which x is smaller than 10 and more inparticular in which x is equal to 3.

The olefinically unsaturated hydrocarbons with the general formula C_(x)H_(y) employed in the preparation of the terpolymers according to theinvention can also be represented by the general formula CHR₁ ═CHR₂where the groups R₁ and R₂ together contain fewer than 18 carbon atomsand where one of the groups R₁ and R₂ is a hydrocarbon group and theother one is hydrogen or also a hydrocarbon group. In the latter case,R₁ and R₂ can together form part of a cyclic structure, such as in themonomers cyclopentylene and cyclohexylene. If the groups R₁ and R₂ arehydrocarbon groups, alkyl groups are preferred. Particularly preferredare monomers in which one of the groups R₁ and R₂ is hydrogen and theother is an alkyl group and more in particular a methyl group.

As mentioned above, the terpolymers according to the invention can beprepared with the aid of a catalyst enabling a linear alternatingcopolymer to be prepared from a mixture of carbon monoxide and ethylene,the copolymer consisting of units with the formula --CO--(C₂ H₄)--.Suitable catalysts for this purpose are the previously mentionedpalladium, nickel and cobalt compounds. Examples of catalysts belongingto this group are alkyl- and arylphosphine complexes of palladium, suchas bis(tributylphosphine)PdCl₂, bis(triphenylphosphine)PdCl₂,allyl(triphenylphosphine)PdCl and tetrakis(triphenylphosphine)Pd,HPd(CN)₃, Ni(CN)₂ and complex nickel salts containing a tetracyanonickelanion, such as bis(tetrabutylammonium)tetracyanonickel.

For the preparation of the terpolymers according to this invention,there is strong preference for the use of catalysts belonging to a classwhich will be described below. These catalysts, which have a much higheractivity than those mentioned above, are obtained by the reaction of aGroup VIII metal compound such as a palladium, cobalt or nickelcompound, with an anion of an acid having a pKa of less than 2, otherthan a hydrohalogenic acid and with a bidentate ligand having thegeneral formula R¹ R² --M--R--M--R³ R⁴, where M represents phosphorus,arsenic or antimony, R¹, R², R³ and R⁴ represent hydrocarbon groups andR represents a bivalent organic bridge group containing at least twocarbon atoms in the bridge. For the sake of brevity, these catalystswill be referred to in the rest of this patent application as "BDL"(bidentate ligand) catalysts.

For the preparation of the terpolymers according to the invention, useis preferably made of a BDL catalyst obtained from a palladium compoundas Group VIII metal compound. Very suitable for this purpose arepalladium salts of carboxylic acids and in particular palladium acetate.Examples of suitable acids with a pKa of less than 2 (measured inaqueous solution at 18° C.) are sulfonic acids such as methanesulfonicacid, trifluoromethanesulfonic acid and para-toluenesulfonic acid andcarboxylic acids such as trichloroacetic acid, difluoroacetic acid andtrifluoroacetic acid. Para-toluenesulfonic acid and trifluoroacetic acidare preferred. For the preparation of the BDL catalysts, the anion ofthe acid with a pKa of less than 2 is preferably present in the mixturein an amount of 0.5 to 200 and more particular of 1.0 to 100 equivalentsper g--at Group VIII metal. M in the bidentate ligand is preferablyphosphorus. The hydrocarbon groups R¹, R², R³ and R⁴ preferably contain6 to 14 carbon atoms. Particularly preferred are bidentate ligands inwhich the hydrocarbon groups R¹, R², R³ and R⁴ are phenyl groups oralkyl-substituted phenyl groups. The bivalent organic bridge group Rpreferably contains three carbon atoms in the bridge. Examples ofsuitable bidentate ligands are: 1,3-bis(di-p-tolylphosphine)propane,1,3-bis(diphenylphosphine)propane, and2-methyl,2-(methyldiphenylphosphine)-1,3-bis(diphenylphosphine)propane.Preferably, one of the two last-mentioned bidentate ligands is employed.In the mixture from which the BDL catalysts are prepared the bidentateligand is preferably present in an amount of 0.1-2 and in particular0.9-1.1 moles per mol. Group VIII metal compound.

The polymerization is preferably carried out in a liquid diluting agent.Lower alcohols such as methanol and ethanol are very suitable as liquiddiluting agents. The quantity of BDL catalyst employed for thepreparation of the polymers according to the invention can vary withinwide limits. Preferably, 10⁻⁷ -10⁻³ and more in particular 10⁻⁶ -10⁻⁴mol. of the BDL catalyst per mol. of the olefinically unsaturatedhydrocarbon to be polymerized is employed. The molar ratio of theolefinically unsaturated hydrocarbons relative to carbon monoxide in themixture to be polymerized is preferably 10:1-1:5 and in particular5:1-1:2. In the monomer mixture from which the terpolymers according tothe invention are prepared the ratio between ethylene and theolefinically unsaturated hydrocarbons with the general formula C_(x)H_(y) should be chosen such that a terpolymer is obtained with thedesired low melting point. The carbon monoxide used in the preparationof the polymers according to the invention does not need to be pure, butmay contain impurities such as hydrogen, carbon dioxide and nitrogen.The terpolymers according to the invention are preferably prepared froma monomer mixture that in addition to carbon monoxide and ethylene alsocontains an olefin with less than 10 carbon atoms and in particularpropylene.

The preparation of the terpolymers with the aid of a BDL catalyst ispreferably performed at a temperature of 20°-150° C. and a pressure of1-200 bar and in particular at a temperature of 30°-100° C. and apressure of 20-100 bar.

As mentioned above, the terpolymers according to the invention haveexcellent mechanical properties, in particular a very high strength,rigidity and impact-resistance. They can be processed by means of theusual techniques into, among other things, films, sheets, plates, fibersand molded objects. On account of their superior properties, thepolymers according to the invention are suitable for many applications,such as in the automobile industry, for the manufacture of packagingmaterial for foods and drinks, as constructional and building material,for the manufacture of cables and for a variety of applications in thedomestic sphere. In order to modify their characteristics or tostrengthen them, the polymers according to the invention can be employedin combination with many other sorts of materials.

The invention will now be illustrated with the aid of the followingexamples.

EXAMPLE 1

A carbon monoxide/ethylene copolymer was prepared as follows. 200 mlmethanol was introduced into a mechanically stirred autoclave with avolume of 300 ml. After the contents of the autoclave had been broughtto a temperature of 85° C., a 1:1 carbon monoxide/ethylene mixture wasintroduced into the autoclave until a pressure of 55 bar was reached. Acatalyst solution was then introduced into the autoclave, consisting of:

6 ml methanol

0.01 mmol palladium acetate

0.01 mmol 1,3-bis(diphenylphosphine)propane, and

0.02 mmol trifluoroacetic acid.

The pressure was maintained at 55 bar by introducing under pressure a1:1 carbon monoxide/ethylene mixture. After 5 hours the polymerizationwas stopped by releasing the pressure. The polymer was filtered off,washed with methanol and dried at 70° C. 30 g copolymer with a meltingpoint of 257° C. and an LVN of 0.85 dl/g was obtained.

EXAMPLE 2

A carbon monoxide/ethylene copolymer was prepared substantially in thesame way as the copolymer in Example 1, except for the followingdifferences:

(a) instead of 1,3-bis(diphenylphospine)propane,2-methyl,2-(methyldiphenylphosphine)-1,3-bis(diphenylphosphine)propanewas used, and

(b) instead of trifluoroacetic acid, p-toluenesulfonic acid was used. 25g copolymer with a melting point of 257° C. and an LVN of 0.58 dl/g wasobtained.

EXAMPLE 3

A carbon monoxide/ethylene copolymer was prepared substantially in thesame way as the copolymer in Example 2, except that in this case insteadof a temperature of 85° C., a temperature of 40° C. was employed. 3 gcopolymer with a melting point of 257° C. and an LVN of 3.3 dl/g wasobtained.

EXAMPLE 4

A carbon monoxide/ethylene/propylene terpolymer was prepared as follows.200 ml methanol and 5 ml liquid propylene was introduced into amechanically stirred autoclave with a volume of 300 ml. After thecontents of the autoclave had been brought to a temperature of 85° C., a1:1 carbon monoxide/ethylene mixture was introduced into the autoclaveuntil a pressure of 55 bar was reached. A catalyst solution was thenintroduced into the autoclave, consisting of:

6 ml methanol

0.01 mmol palladium acetate

0.01 mmol of 1,3-bis(diphenylphosphine)propane, and

0.2 mmol trifluoroacetic acid.

The pressure was maintained at 55 bar by introducing under pressure a1:1 carbon monoxide/ethylene mixture. After 7 hours the polymerizationwas stopped by releasing the pressure. The polymer was filtered off,washed with methanol and dried at 70° C. 21 g terpolymer with a meltingpoint of 238° C. and an LVN of 0.55 dl/g was obtained.

EXAMPLE 5

A carbon monoxide/ethylene/propylene terpolymer was preparedsubstantially in the same way as the terpolymer in Example 4, except forthe following differences:

(a) instead of 5 ml liquid propylene, 20 ml of this compound was used,and

(b) instead of the polymerization being stopped after 7 hours, it wasstopped after 4 hours.

21 g terpolymer with a melting point of 220° C. and an LVN of 0.4 dl/gwas obtained.

EXAMPLE 6

A carbon monoxide/ethylene/propylene terpolymer was preparedsubstantially in the same way as the terpolymer in Example 4, except forthe following differences:

(a) instead of 5 ml of liquid propylene, 50 ml of this compound wasused,

(b) instead of a temperature of 85° C., a temperature of 60° C. wasused,

(c) instead of a pressure of 55 bar, a pressure of 45 bar was used, and

(d) instead of the polymerization being stopped after 7 hours, it wasstopped after 5 hours.

5 g terpolymer with a melting point of 214° C. and an LVN of 0.7 dl/gwas obtained.

EXAMPLE 7

A carbon monoxide/ethylene/propylene terpolymer was preparedsubstantially in the same way as the terpolymer in Example 4, except forthe following differences:

(a) instead of 5 ml of liquid propylene, 45 ml of this compound wasused,

(b) instead of a temperature of 85° C., a temperature of 45° C. wasused,

(c) instead of a pressure of 55 bar, a pressure of 45 bar was used,

(d) for pressurizing the autoclave, instead of a carbonmonoxide/ethylene mixture with a mol. ratio of 1:1 being applied, asimilar mixture with a mol. ratio of 3:1 was used, and

(e) instead of the polymerization being stopped after 7 hours, it wasstopped after 5 hours.

1 g terpolymer with a melting point of 178° C. and an LVN of 1.4 dl/gwas obtained.

EXAMPLE 8

A carbon monoxide/ethylene/butene-1 terpolymer was preparedsubstantially in the same way as the terpolymer in Example 4, except forthe following differences:

(a) instead of 5 ml of propylene, 20 ml of liquid butylene-1 was used,and

(b) instead of the polymerization being stopped after 7 hours, it wasstopped after 4 hours.

24 g terpolymer with a melting point of 244° C. and an LVN of 0.6 dl/gwas obtained.

EXAMPLE 9

A carbon monoxide/ethylene/octylene-1 terpolymer was preparedsubstantially in the same way as the terpolymer in Example 4, except forthe following differences:

(a) instead of 5 ml of propylene, 39 ml of octylene-1 was used, and

(b) twice the quantity of the catalyst solution was used, and

(c) instead of the polymerization being stopped after 7 hours, it wasstopped after 19 hours.

19 g terpolymer with a melting point of 225° C. and an LVN of 0.28 dl/gwas obtained.

Of the polymers according to Examples 1-9, only the terpolymersaccording to Examples 4-9 are polymers according to the invention. Thecopolymers prepared according to Examples 1-3 fall outside the scope ofthe invention and are included in the patent application for comparison.

With the aid of ¹³ C-NMR analysis it was established that the carbonmonoxide/ethylene copolymers prepared according to Examples 1-3 had alinear alternating structure and they they consisted of units with theformula --CO--(C₂ H₄)--. As can be seen from the Example 1-3, the threecopolymers all had different LVN values all had a melting point of 257°C., although they were prepared by different methods.

It was also established with the aid of ¹³ C-NMR analysis that thecarbon monoxide/ethylene/propylene terpolymers prepared according toExamples 4-7 had a linear structure and that they consisted of unitswith the formula --CO--(C₂ H₄)-- and units with the formula --CO--(C₃H₆)--, which units were distributed in a random manner in theterpolymers. On the basis of the data from the ¹³ C-NMR analysis, thevalue of the m/n quotient was determined for each of the terpolymersprepared according to Examples 4-7. These values are given in the table.As can be seen, the higher the value of the m/n quotient, the lower themelting point of the terpolymer.

Finally, it was also established by means of ¹³ C-NMR analysis that thecarbon monoxide/ethylene/butylene-1 and the carbonmonoxide/ethylene/octylene-1 terpolymers prepared according to Examples8 and 9 had a linear structure and that they consisted of units with theformula --CO--(C₂ H₄)-- and units with the formula --CO--(C₄ H₈)-- and--CO--(C₈ H₁₆)-- respectively, these units being distributed in theterpolymers in a random manner. From the ¹³ C-NMR analysis data, thevalue of the m/n quotient was also determined for the terpolymersprepared according to Examples 8 and 9. These values are also given inthe table.

                  TABLE                                                           ______________________________________                                                                    melting                                                                       point                                                                    m/n  °C.                                        ______________________________________                                        CO/C.sub.2 /C.sub.3 terpolymer according to Example 4                                                  0.030  238                                           CO/C.sub.2 /C.sub.3 terpolymer according to Example 5                                                  0.073  220                                           CO/C.sub.2 /C.sub.3 terpolymer according to Example 6                                                  0.104  214                                           CO/C.sub.2 /C.sub.3 terpolymer according to Example 7                                                  0.235  178                                           CO/C.sub.2 /C.sub.4 terpolymer according to Example 8                                                  0.007  244                                           CO/C.sub.2 /C.sub.8 terpolymer according to Example 9                                                  0.057  225                                           ______________________________________                                    

From the carbon monoxide/ethylene copolymer with melting point 257° C.prepared according to Example 3 a plate was pressed for 15 minutes at285° C. This resulted in complete gelling (100%) of the copolymer and avery strong yellow discoloration.

From the carbon monoxide/ethylene/propylene terpolymer with meltingpoint 214° C. prepared according to Example 6 a plate was also pressedfor 15 minutes, but this time at 240° C. In this case there was nogelling (less than 0.5%) and hardly and discoloration.

The degree of gelling of the polymers is determined by taking up 100 mgpolymer in 50 ml m-cresol at 100° C. and filtering the mixture over a75μ filter. The degree of gelling is specified as the weight percentageof the polymer remaining on the filter.

What is claimed is:
 1. A linear polymer consisting essentially of an average of n units with the formula --CO--(C₂ H₄)-- and an average of m units with the general formula --CO--(C_(x) H_(y))-- wherein the units are randomly distributed in the polymer, the quotient m/n is between about 0.33 and about 0.007, x is greater than 2 and less than 20, y is 2x, and the polymer has a melting point between about 150° C. and 245° C.
 2. A linear polymer consisting of an average of n repeating units of the formula --CO--(C₂ H₄)-- and an average of m repeating units of the formula --CO--(C₃ H₆)--, wherein the units are randomly distributed in the polymer, said polymer having an m/n quotient between about 0.33 and about 0.023, and said polymer having a melting point between about 150° C. and 245° C.
 3. The polymer of claim 1 having a melting point between about 170° C. and about 240° C.
 4. The polymer of claim 1 having a melting point between about 195° C. and about 235° C.
 5. The polymer of claim 1 having a Limiting Viscosity Number in m-cresol at 100° C. between about 0.2 and 5.0 dl/g.
 6. The polymer of claim 1 having an Limiting Viscosity Number in m-cresol at 100° C. between about 0.3 and 4.5 dl/g.
 7. The polymer of claim 1 having an Limiting Viscosity Number in m-cresol at 100° C. between about 0.4 and 4.0 dl/g.
 8. The polymer of claim 1 having units with the general formula --CO--(C_(x) H_(y))--, where x is greater than 2 and less than
 10. 9. The polymer of claim 1 having units with the formula --CO--(C₂ H₄)-- and units with the formula --CO--(C₃ H₆)--.
 10. The polymer of claim 1 having units with the formula --CO--(C₂ H₄)-- and units with the formula --CO--(C₄ H₈)--.
 11. The polymer of claim 1 having units with the formula --CO--(C₂ H₄)-- and units with the formula --CO--(C₈ H₁₆)--.
 12. An article of manufacture comprising a linear polymer consisting essentially of an average of n units with the formula --CO--(C₂ H₄)-- and an average of m units with the general formula --CO--(C_(x) H_(y))-- wherein the units are randomly distributed in the polymer, the quotient m/n is between about 0.33 and about 0.007, x is greater than 2 and less than 20, y is 2x, and the polymer has a melting point between about 150° C. and 245° C.
 13. An article of manufacture comprising a linear polymer consisting of an average of n repeating units of the formula --CO--(C₂ H₄)-- and an average of m repeating units of the formula --CO--(C₃ H₆)--, wherein the units are randomly distributed in the polymer, said polymer having an m/n quotient between 0.33 and about 0.023, and said polymer having a melting point between about 150° C. and 245° C.
 14. The article of claim 12, wherein the polymer has a melting point between about 170° C. and 240° C. 